1. Field of the Invention
The present invention relates to an electrical connector for electrically connecting an electronic package such as a central processing unit (CPU) with a circuit substrate such as a printed circuit board (PCB), and particularly to an electrical connector with a strengthened actuation device that actuates connection and disconnection of the CPU with and from the electrical connector.
2. Description of Prior Art
Electrical connectors are widely used in personal computer (PC) systems for electrically connecting electronic packages such as CPUs with circuit substrates such as PCBs. Typical such electrical connectors are known as CPU sockets. A typical CPU socket comprises a base soldered and electrically connected with the PCB, a cover slidably attached on the base and having a CPU attached thereon, and an actuation device assembled between the base and the cover for actuating the cover to slide along the base.
The CPU has a multiplicity of pins depending from a bottom surface thereof and arranged in a rectangular array. The cover of the CPU socket has a multiplicity of through holes arranged in a rectangular array corresponding to the pins of the CPU. The base of the CPU socket has a multiplicity of passageways arranged in a rectangular array corresponding to the pins of the CPU. Each passageway receives an electrical terminal therein.
In use, the cover is at an open position with respect to the base. Then, the CPU is attached to the CPU socket. The pins of the CPU extend through the corresponding through holes of the cover and are received in the corresponding passageways of the base. The pins of the CPU do not contact corresponding electrical terminals. Thus the CPU is attached with zero insertion force. In particular, the pins of the CPU are prevented from being flexed by sudden force being applied thereto by the electrical terminals. Then, the actuation device actuates the cover to slide along the base. When the cover reaches a closed position with respect to the base, the actuation device pushes the pins of the CPU into mechanical and electrical engagement with the corresponding electrical terminals.
This kind of conventional CPU socket is detailed in “Development of ZIF BGA Socket” (pp 16˜18, May 2000, Connector Specifier Journal). This kind of conventional CPU socket is also disclosed in U.S. Pat. No. 6,340,309.
FIG. 7 shows a conventional LGA connector 6 for electrically connecting a CPU (not shown) with a PCB (not shown). The connector 6 comprises a generally rectangular insulative base 60, a cover 61 slidably attached on the base 60, and an actuation device 62 assembled between the base 60 and the cover 61 for actuating the cover 61 to slide along the base 60.
The base 60 comprises a main portion 600, and a front portion 601 integrally extending from the main portion 600. The main portion 600 defines a multiplicity of receiving passageways 6000 arranged in a rectangular array. Each passageway 6000 receives an electrical terminal 63 therein, and the electrical terminals 63 are electrically connected with the PCB. The front portion 601 defines a locating slot therein and a pair of spaced windows 6013 at an outward side thereof. The front portion 601 forms a first and a second receiving portions 6011a, 6011b at respective opposite ends of the locating slot, and a central third receiving portion 6011c between the first and second receiving portions 6011a, 6011b. The third receiving portion 6011c defines a locating step 6012 thereon nearest the main portion 600. In view of the window 6013 adjacent to the first receiving portion 6011a, the first receiving portion 6011a is cantilever-shaped.
The cover 61 defines a multiplicity of through holes 610 arranged in a rectangular array corresponding to the receiving passageways 6000 of the base 60. The cover 61 further comprises a pair of locks 611 engaging in corresponding windows 6013 of the front portion 601 of the base 60.
The actuation device comprises a camshaft 620 and an operation lever 621 extends perpendicularly from one end of the camshaft 620. The camshaft 620 forms a first and a second supporting portions 6200a, 6200b at respective opposite ends thereof, and a central third supporting portion 6200c between the first and second supporting portions 6200a, 6200b. The first, second and third supporting portion 6200a, 6200b, 6200c are respectively rotatablely received in the first, second and third receiving portions 6011a, 6011b, 6011c. The third supporting portion 6200c defines a locating block 6201 thereon corresponding to the locating step 6012 of the third receiving portion 6011c of the base 60.
In use, the cover 61 is at an open position with respect to the base 60. At this position, the locating block 6201 of the camshaft 620 engages with the locating step 6012 of the third receiving portion 6011c of the base 60, thereby the operation lever 621 is positioned perpendicularly to the base 60. Then, the CPU is attached to the connector 6. The pins of the CPU extend through corresponding through holes 610 of the cover 61 and are received in corresponding passageways 6000 of the base 60. The pins of the CPU do not contact with corresponding electrical terminals 63. Thus, the CPU is attached with zero insertion force. Then, the actuation device 62 actuates the cover 61 to slide along the base 60. When the cover 61 reaches a closed position with respect to the base 60, the actuation device 62 pushes the pins of the CPU into mechanical and electrical engagement with corresponding electrical terminals 63. At this position, the operation lever 621 is parallel to the base 60.
When the CPU is attached on or removed from the connector 6, the operation lever 621 is rotated upwardly to a position perpendicular to the base 60. In this process, the operation lever is prone to be accidentally over-rotated beyond said perpendicular position. When this happens, the first supporting portion 6200a of the camshaft 620 applies a force to the locating slot 6010 at the first receiving portion 6011a. Because the first receiving portion 6011a is cantilever-shaped, a tension of the first receiving portion 6011a is reduced. When the force is applied on the first receiving portion 6011a, the first receiving portion 6011a is prone to be destroyed. This results in the locating slot 6010 being destroyed.
A new electrical connector that overcomes the above-mentioned disadvantages is desired.